The LONG-TERM OBJECTIVE of this proposal is to conduct a case-control study to investigate the role of oral contraceptives (OC's) in the etiology of adenocarcinoma of the uterine cervix. The SPECIFIC AIMS are (1) to determine if the risk of cervical adenocarcinoma is increased by OC use (especially use before age 20); (2) to determine if risk increases with increasing duration of OC use, decreasing age at first use, or the particular formulation of OC used; (3) to identify other risk factors for this tumor, focusing both on other hormonal exposures such as intrauterine exposure to DES, obesity, and nulliparity, and on risk factors important in squamous cell carcinoma of the cervix such as sexual factors, genital infections, and smoking; (4) to determine if any increased risk due to OC use is modified by other risk factors for this tumor; (5) to determine if any risk factors for this tumor are specific for histologic subcategories of cervical adenocarcinoma; and (6) to establish the reliability of self-reported OC use and self-reported intrauterine exposure to DES. METHODS: A matched case-control study design will be used with two neighborhood controls per case. Case will be 300 English-speaking, white or black women born in 1935 or later, diagnosed with adenocarcinoma of the cervix between 1980 and 1990, and identified by the Los Angeles County/USC Cancer Surveillance Program (CSP). Controls will be matched on sex, race and year of birth (within 3 years). Data will be obtained by personal interviews in subjects; homes using a structured questionnaire and, to facilitate recall, a month-by-month calendar and photo album showing all OC's ever sold in the U.S. Mothers of both cases and controls will be inverviewed by telephone to ascertain intrauterine hormone exposures, and the diagnostic slides of all eligible cases will be requested and re-classified using consistent criteria. Finally, validation of OC use by the prescribing physicians and/or clinics will be requested and this information compared to the self-reported data.